This project proposes to investigate the role of the M1 metallo- aminopeptidase gene family in the cellular physiology of the yeast Saccharomyces cerevisiae. Although aminopeptidase genes or gene products are thought to be involved in a number of disease states (small lung cell carcinomas, renal carcinomas, pre-B cell lymphomas, and others), not much is understood about their role in cellular physiology. Using the power of yeast genetics, strains will be developed containing one or more M1 metallo-aminopeptidase genes disrupted. The strains will be analyzed for defects ingrowth, physiology, and response to stress. The project will use genefusion and fluorescent microscopy techniques to localized the gene products in the cell. The project will also analyze two of the metallo-aminopeptidase gene products that have not been isolated or characterized in their activity and specificity. Finally, the project will isolate suppressors of the phenotypic lesions casued by metallo-aminopeptidase gene disruptions. This will allow analysis of how the metallo-aminopeptidase cause the changes in the cell. The elucidation of aminopeptidase function is important in understanding how aminopeptidases may be involved in the diseases above.